Grinder



Feb. 1, 193s. H, J, CRWER 2,107,105

lGRINDER Filed July 29, 1937 2 Sheets-Sheet l ATTORNEYS H. J. CRINER Feb. l, 1938.

GRINDER Filled July 29, 1937 2 Sheets-Sheet 2 1N VENTOR.

VBY

ATTORNEYS.

Patented Feb. 1, 1938 UNITED-,STATES PATENT OFFICE GRINDER Harry J. Criner, Davenport,I Iowa, assignmof one-half to A. Bush, Davenport, Iowa Applioation July 29, V1937, serial No. 156,331 '7V Claims. (ol. 51432) My invention relates to improvements in grindrigidly secured by a set screw, 1', or other suiters for slicing blades, such as the scallopedblades able means. commonly used in bread slicing machines. Upon the opposite end of the shaft, I'I, I mount The objects of my invention are tov provide an a square head, 20, rigidly secured to the shaft, 5 economical, eilicient grinding machine by which I'I, by a pin or bolt, 22. In the upper and lower the slicing blades of a bread slicer may be ground faces of the head, 20, I cut slots in which keys, 2l without removing the blades from the reciprocatand 2I are rigidly secured. ing frame commonly used to support and drive Intermediate the hub, 1, and the head, 23, I the blades during the cutting operation; also, to mount slidin-gly upon the shaft, I'I, a sleeve, I4, afford means for successively grinding a plurality having a collar, I4', formed integral with one end l0 of blades mounted in a suitable retaining frame thereof. This sleeve, I4, is tubular, but may be or for grinding a single blade so held. eccentric to the shaft, I1, so that by rotating My apparatus is designed primarily for sharpeither theV sleeve, I4, or the shaft, I'I, the height ening used blades rather than for the original of the bearings mounted upon the sleeve, I4, may

l5 grinding of blades, although it is obvious that be varied. l5l it may be adapted for the original grinding of I prefer to mountvv the shaft, I'I, in the hub, l, blades if desired. with a set screw, 1', in such manner that the set I attain these objects by the means illustrated screw may be loosened and the shaft, I7, rotated in the accompanying drawings, in which,' to any desired angle. The set screw, 1', may be Figure 1 is a vertical section-ofmy machine on then tightened andthe shaft' rigidly secured in 20 the line I-I of FigureZ; its rotated position. l Figure 2 is a plan view of my machine; In the shaft, I1, I cut a longitudinal slot, I5,

' ligure' is a cross-section on the line 3--3 of into which the inner end of a set screw, I6, pro- Figure 1; e jects, the set screw being threaded in the sleeve,

Figure 4 is an enlarged sectional detail 0n the I4.V The-slot, I5, is made somewhat wider than 25 line 4 4 of Figure 1; the diameter of the set screw, I 6, as shown in Figure 5 is anv enlargeddetail elevation of an Figure 2, so as to permit a limited rotational alternate form 0f my machine in which thegrindmovement thereof, the extent of such rotational er shaft and'motor shaft are integral;` movement depending upon the width of the slot, Figure 6' is a plan View' of theform shownV in I5', and the relative diameter of the pin or set 30 Figure 5. screw, I6.

In FiguresZ and 4, I have shown a portion of UponA the sleeve, I4, I mount at either end,

a rectangular head frame, 40, such as is combearings, 2 and 3. The bearing, 2, is preferably monly used in slicing machines, but for clear-` Secured 120th@ Sleeve, I4, by a Set SCIEW, 2. The ness I have omitted this head frame in Figure l. bearing, 3, has secured in the upper face thereof 35 Similar numerals refer to similar parts a handle, 6, which may be formed integral with throughout the several views. the bearing, 3, or suitably united thereto.

My apparatus comprises a support, II, which EXtending dOWIlWIdlY fl'Om the bearings, 2 and is preferably a round shaft orv column having a 3, I fOlm integral With the bearings, arms, 4 and 4o sndablo foot, i2, united to the lower end thereof 5, Which Carry a cylinder, I, or a motor housing, 40 by a pin, I2', adapted to restupon a table or counl", 11n Which a' Shaft 331 1S mounted upon bau' ter,.I3, or other suitable base. The foot, I2, may bef'mngs 38 31nd 33'- Thls Shaftf 33 may be be a small circular foot, as shown at I2 in Figdnven by a dmv? Shaft" 34?, suitably connected to ure 1! or it may have an extended base, |2 the rear end thereof, or 1t may form a motor unitedthereto'as shown iii-,Figures 5 and 6. Shaft for the motor I 45 The shaft 33, extends forwardly andV has its Upon the support, I I, I mount a sleeve, 8, which is sudableeupon the support, H andmay be se forward end threaded at 3| to mesh with threads,

cured in place by a thumb screw III at an 30' formed upon a bushing upon which the y grinder head, 29, is rigidly mounted. Dust plates, helght necessary to correspond to the height of 39 and 39" may be Secured in Opposite ends of 50 the various blades on a given set of blades, 24, thehousmg, if desired` The grinder head, 2g, Secured in the head frame, 40- is made in cylindrical form with a diameter small To the inner side of the sleeve, 8, may beunited enough to permit it to pass between adjacent a bracket or arm, 9, carrying a hub', 'I, in which blades in the slioer frame, which ordinarily are one, end of a laterallyr extendingv shaft, H, is from three-quarters of an inch to an inch apart, 55

according to present practice, but the size and proportions of the grinding head, 29, may be varied to suit the requirements of different cases. The grinding head, 29, is preferably made of carborundum, but may be formed of any suitable abrasive material desired.

The drive shaft, 34, may be driven by an individual motor mounted thereon or by any other desired means permitting the necessary flexibility.

A rectangular head frame, I8, is formed with parallel rearwardly projecting flanges, I 8 and I8, which have parallel slots, I9, cut in them into which the keys, 2I and 2I, may enter.

'Ihe outer ends of the frame, I8, are extended downwardly and forwardlyand formed integral with a supporting plate, 25, leaving an opening, 28, through which the grinding head, 29, may pass and operate. The supporting plate, 25, extends the full length of the frame, I8, and has a clamping plate, 26, united thereto by thumb screws, 21, or other suitable means.

In the operation of my machine the supporting plate, 25, and clamping plate, 26, are rigidly secured to one of the blades, 24, which are to be sharpened, the blades, 24, being held securely in a blade frame, 40, which may be the usual type of removable blade frame 1n common use in bread slicing machines, or a special frame in which the blades may be mounted merely for the purpose of being ground.

The frame, 4D, will preferably rest upon the same table or counter as the grinding apparatus, but may be supported in juxtaposition thereto in any desired manner.

The grinding apparatus will then be moved into position so that the keys, 2| and 2|', are in their proper position in opposed slots, I9. These slots are made of suflicient length to insure the shaft, I'I, standing at right angles to the head frame, I8, and to the blades, 24.

The sleeve, I4, is then slid forward on the shaft, I'I, so as to bring the grinder into contact with one of the scallops of lthe cutting blade. The handle, 6, is then swung from side to side, thereby swinging the grinder through an arc equal to the length of one scallop on the blade, and a grinding head may be simultaneously caused to travel longitudinally so as to present successive portions thereof in contact With the blade. It will be understood that the blades are mounted upon the supporting bar, 25,k in such position that the middle of each scallop is directly in line with the middle of its corresponding slots, I 9, and the length of the arms, 4 and 5, and the height of the shaft, 32., in the cylinder, I, is so regulated that this arc will correspond to the ground faces of the scallops.

In re-sharpening blades, it will be understood that only a very small portion of the metal is to be taken off--ordina-rily one-thousandth of an inch is ample for this purpose and the grinding heads shown will sharpen a large number of blades without appreciable wear, but when Worn, may be thrown away and replaced with new, as they are very inexpensive.

While I have shown the sleeve, 8, securable in position by a set screw, I0, it is obvious that any desired form of adjustment may be utilized to regulate the heighth of the shaft, I'I.

It is also obviousthat as the adjustment of the eccentric sleeve, I4, varies the relative position of the cylinder, I, and the arc of travel of the grinding head, 29, kthe relative position of the supporting plate, 25, upon the blade, 24, may be varied so as to secure the proper allnement of the grinding head and the scallops of the blades.

I have shown a readily applied clamp to secure the blades and the head frame, but in the case of steel cutting blades, the supporting bar, 25, may be of steel or iron and magnetized so as to hold the blades rmly by magnetic attraction while being ground, or any other desired form of attachment may be used. Y

I do not limit my claims to the precise forms of parts shown in the drawings, because it is obvious many modifications thereof may be made Without departing from the spirit of my invention.

I claim:

1. A grinding machine for sharpening scalloped blades, comprising a base, a supporting column secured thereto, a sleeve adjustably mounted upon the column supporting a transverse shaft and rigidly united thereto, a sleeve slidingly mounted upon the shaft and rotatable thereon, a shaft housing parallel with and carried by the sleeve and spaced therefrom, a grinder shaft revolvably mounted in the housing and carrying a cylindrical grinding head mounted thereon extending forwardly from the housing, and means to secure a scalloped slicing blade in juxtaposition to the grinding head.

2. A grinding machine for sharpening scalloped blades, comprising a base, a supporting column secured thereto, a sleeve adjustably mounted upon the column supporting a transverse bar and rigidly united thereto, a block united to the free end of the bar carrying a key rigidly secured therein, a sleeve slidingly mounted upon `the shaft and rotatable thereon, a shaft housing parallel with the sleeve and spaced therefrom, a grinder shaft revolvably mounted in the housing and carrying a cylindrical grinding head mountedthereon extending forwardly from the housing in combination with a head frame having successive slots formed therein adapted to receive the key, and means to secure the head frame in fixed spaced position relative to blade to be sharpened.

3. A grinding machine for sharpening scalloped blades, comprising a base, a supporting column secured thereto, a sleeve adjustably mounted upon the column supporting a transverse bar and rigidly kunited thereto, an eccentric sleeve slidingly mounted upon the bar and rotatable thereon, a shaft mounted parallel with and carried by the sleeve and spaced therefrom adapted to swing through a limited arc of travel corresponding to the arc of the blade scallops, a small diameter elongated cylindrical grinding head mounted on a forwardly extending end of said shaft, means to secure a slicing blade With its scallops in successive juxtaposition to the grinding head, and contacting lightly therewith, and means to secure the eccentric sleeve in various adjusted positions on its bar.

4. A grinding machine for sharpening scalloped blades, comprising a base, a supporting column secured thereto, a sleeve adjustably mounted upon the column supporting a transverse bar and rigidly united thereto, a sleeve slidingly mounted upon the bar and rotatable thereon, a shaft mounted parallel with and carried by the sleeve and spaced therefromvadapted to swing through a limited Yarc of travelv corresponding to the arc of theblade scallops, a small diameter elongated cylindrical grinding head mounted on a forwardly extending end of said shaft, means to secure a slicing blade With its scallops in successive juxtalll) position to the grinding head, and contacting lightly therewith.

5. In a grinding machine for sharpening scalloped bread slicing blades, the combination with a suitable support, of rotatable grinding means carried by said support and pivotally united thereto to swing in a predetermined arc therefrom, corresponding to the arc of the beveled portion of the scallops in the blades to be ground, means for securing said grinder in a succession of spaced positions corresponding to the scallops of the blades to be ground, means for rigidly securing the blade to be ground in a straight line and in position with a beveled face of a given scallop in the arc of travel of the periphery of said grinding means and in light contact therewith, and means for driving such grinding means both rotationally and longitudinally while being swung through the above described arc.

6. A grinding machine for sharpening scalloped blades, comprising a base, a supporting column secured thereto, a sleeve adjustably mounted upon the column supporting a transverse shaft and rigidly united thereto, a sleeve slidingly mounted upon the shaft and rotatable thereon, a shaft housing parallel with and carried by the sleeve and spaced therefrom, a grinder shaft revolvably mounted in the housing and carrying a cylindrical grinding head mounted thereon extending forwardly from the housing, in combination with a spacing head and blade holder comprising a pair of clamping plates with means for securing them to the rear edge of a blade to be ground, arms united to the opposite ends of one of said plates, a spacing head united to the arms parallel to the clamping plates, and spac ing means formed in said spacing head adapted to register with the scallops of a scalloped blade secured in said clamping means, and secure such blade in position to be acted upon by said grinding head.

7. A grinding machine for sharpening scalloped blades, comprising a base, a supporting column secured thereto, a sleeve adjustably mounted upon the column supporting a transverse shaft and rigidly united thereto, a sleeve slidingly mounted upon the shaft and rotatable thereon, a shaft housing parallel with and carried by the sleeve and spaced therefrom, a grinder shaft revolvably mounted in the housing and carrying a cylindrical grinding head mounted thereon extending forwardly from the housing, in combination with a spacing head and blade holder comprising a pair of clamping plates with means for securing them to the rear edge of a blade to be ground, arms united to the opposite ends of one of said plates, a spacing head united to the arms parallel to the clamping plates, and slots formed in said spacing head adapted to register with the scallops of a scalloped blade secured in said clamping means and secure such blade in position to be acted upon by said grinding head.

HARRY J. CRINER. 

